1. Field of the Disclosure
The present disclosure is generally directed to abrasive particulate material, methods for making abrasive particulate material, abrasive products incorporating abrasive particulate material, and methods for machining workpieces with abrasive particulate material.
2. Description of the Related Art
Abrasive products generally contain or are formed from abrasive particulate material. Such abrasive particulate material can be used as a free abrasive, such as in the form of a slurry, or a fixed abrasive, typically either a coated abrasive or a bonded abrasive article. Abrasive products are used in various industries to machine workpieces, such as by lapping, grinding, or polishing. Machining utilizing abrasive articles spans a wide industrial scope including metal fabrication industries. Machining, such as by hand or with use of commonly available tools such as orbital polishers (both random and fixed axis), and belt and vibratory sanders, is also commonly done by consumers in household applications. In each of these examples, abrasives are used to remove bulk material and/or affect surface characteristics of products (e.g., planarity, surface roughness).
Surface characteristics include shine, texture, and uniformity. For example, manufacturers of metal components use abrasive articles to fine polish surfaces, and oftentimes desire a uniformly smooth surface. Similarly, optics manufacturers desire abrasive articles that produce defect free surfaces to prevent light diffraction and scattering. Hence, the abrasive surface of the abrasive article generally influences surface quality.
Manufacturers also desire abrasive articles that have a high stock removal rate for certain applications. However, there is often a trade off between removal rate and surface quality. Finer grain abrasive articles typically produce smoother surfaces, yet have a lower stock removal rate. Lower stock removal rates lead to slower production and increased cost.
The surface characteristics and material removal rate can also be affected by the durability of the abrasive article. Abrasive articles that wear easily or lose grains can exhibit both a low material removal rate and can cause surface defects. Quick wear on the abrasive article can lead to a reduction in material removal rate, resulting in frequent exchanging of the abrasive article. Further, unwanted surface defects can lead to additional polishing steps. Both frequent exchanging of abrasive articles and additional polishing steps lead to slower production and increased waste associated with discarded abrasive articles.
Abrasive particle formation, such as through chemical synthesis routes or through bulk material processing routes (e.g., fusion and comminution), is considered a fairly well developed and mature art area. Accordingly, notable developmental resources have been dedicated to development of macrostructures, such as development of engineered abrasives products within the context of coated abrasives and particular three-dimensional structures and formulations in the context of bonded abrasives. Despite continued developments, a need continues to exist in the art for improved particulate material.
Abrasive particulate materials include essentially single phase inorganic materials, such as alumina, silicon carbide, silica, ceria, and harder, high performance superabrasive grains such as cubic boron nitride and diamond. Enhanced and even more sophisticated abrasive properties have been achieved through development of composite particulate materials. Such materials include formation of aggregates, which can be formed through slurry processing pathways that include removal of the liquid carrier through volatilization or evaporation, leaving behind green agglomerates, followed by high temperature treatment (i.e., firing) to form usable, fired agglomerates.
Additionally, certain aggregates relying on phenolic resin systems have been employed, but typical cross-linking agents release formaldehyde, which poses a risk to workers and is subject to greater environmental regulation.
Such composite agglomerates have found commercial use in various abrasive product deployments. However, the industry continues to demand even further improved particulate materials, and particularly composite aggregates that may offer enhanced machining performance.